Induction coil



Sept. 9,1930. c. F. REIS 1,775,600

INDUCTION CQIL Filed-April 9, 1928 IHHHI I N V EN TOR. Carri Ifieals.

A TTORNEYS Patented Sept. 9, 1930 UNITED STATES PATENT OFFICE CUB/1FREDERICK -REIS, OF CHICAGO, ILLINOIS, ASSIGNOR TO EXCEL MAGNETO 00., OF

CHICAGO, ILLINOIS INDUCTION COIL Application filed April 9, 1928.

My invention relates to induction coils, and

particularly to induction coils adapted for use in automobile ignitionsystems.

One object of my invention is to provide a compact coil which may beassembled without the use of numerous screws and bolts.

Another object is to construct a coil which may readily be adapted touse in diiterent sized units and in which the inclosi'ng casing is aunit.

Another object is to construct a highly efficient coil which isremarkably tree from. electrical break-downs. I g

I will describe one form of induction coil embodying my invention andthen point out the novel features in claims.

In the accompanying drawing, Figure 1 is a side View of one form ofinduction coil embodying my invention.

Figure 2 is a view similar to Figure 1, with parts broken away to showthe interior construction.

Figure 3 is a diagrammatic view showing one form of circuit in which mycoil may be used.

Referring to Figs. 1 and 2 the reference character 1 is a generaldesignation applied to my coil. This coil is made up of a straight coreportion 2 and a curved core portion 3, each composed of many thinstrands of fine soft iron wire so as to reduce the reluctance of themagnetic circuit and minimize losses due to hysteresis and eddycurrents. The core portion 2 carries a primary winding 4 and two spaced,separately wound secondary windings 5 and 6. Primary l closely embracesthe core portion 2 and carries the secondaries 5 and 6. The subdivisionof the core into many fine wires increases the magnetic induction 01 thestraight core, and the induction is still further increased by thepresence of the curved core portion 3. As here shown, the core portions2 and 3 are separated by small air-gaps 7 which increase I the leakagereactance of the windings on core portion 2, and hence increase the timeconstant of the secondary circuit to prevent too sudden decay of thecurrent in this circuit. This insures that the duration of the peakvoltage in the secondary circuit shall Serial No. 268,549.

be suflicient to ignite the explosive charge in the engine cylinder towhich current is being s plied. Vindings l, and 6 are suitably insulatedfrom each other and from the core portion 2, but in order to decreasethe possibility of electrical break-down due to high voltage dischargespuncturing the secondary insulation, coils 5 and 6 are tightlysurrounded by metal bands 8 and 9 respectively.

It is necessary to provide an inclosing casing for the coil parts, and abase for supporting them and for this purpose I inclose the core portion2 including coils 4, 5 and 6 in a cast metal shell 10, preferably ofaluminum. This shell 10 closely embraces all of the parts to hold themin rigid assembled position and is suitably arranged to provide a basewhich serves as a mounting for the entire coil structure. Core portion 3is likewise inclosed in a cast aluminum shell 11, and the two shells 10and 11 are secured in assembled relation by any suitable means, hereshown as screws 12. Casing 10 not only incloses core portion 2 and thewindings 4, 5 and 6 but it carries integral terminal extensions 13 and14. Passing through the extension 13 is a conducting rod 15 connected toone end of primary l. Between the terminal 15 and the winding 4: is aregulating resistance 16.

diiierent arrangements of the secondary cir-.

cuit as will be pointed out later. As shown in Fig. 2 the shell 10carries an integral extension. 19 provided with two terminal connections20 and L3. Terminal 20 is connected. to metal band 8 by a conductingstrip 21 and band 8 in turn connected to secondary 5 by astrip 22. Insimilar manner terminal 23 is connected to band 9' by a strip 24, andband switch 30.

9 is connected to secondary 6 by a strip 25. A plug 26 containing acable 2'? affords means for making a connection to either terminal 20 or23.

It will now be clear that the primary circuit may be completed byconnecting a source of current to terminal eiltension 13 and oneterminal'of circuit breaker to extension l l, the other terminal beinggrounded. This is more clearly shown in Fig. 3. In this figure a battery28 has one terminal grounded at 29 and the other connected to primary 4by a The other terminal of primary t is connected to ground at 32through a circuit breaker 31. The secondary circuit from the upperterminal of coil 5 passes toa distributor and thence to ground throughthe spark plugs of the engine, while the lower terninal may be connectedto ground 36 or to a second distributor 37 by means of-a switch Vi henthe switch 35 is in the vertical position two sparks are produced in thesecondary circuit through distributors and 37 but when the switch 85 isconnected to ground the full voltage of both secondaries 5 and 6 issupplied to distributor It will be understood that the switch. 35 may beconnected to terminal 23 by a suitable plug while the plug 26 isconnected to terminal 20.

My apparatus is not only capable of producin a strong intense spark, butat the same time it is of simple construction and can be assembledwithout the use of screwsother than in fastening the shells 10 and 11.lhe uecessi y for drilling is therefore obviated and assembly costsreduced to a minimum. It should be noted that this coil may be made invarious sizes by simply changing the size of the magnetic core tocorrespond to the size of winding employed. The inclosing shells maythen be cast in place without any special provision other than aditt'erent sized mold.

Although I have herein shown and de scribed only one form of inductioncoil eml'iodyiug my invention it will be understood of a straightportion and a curved portion separatedby air gaps, a plurality ofwindmgs on said straight portion and a one-piece cast aluminum shellencasing each of said core portions.

3. An induction coil comprising a straight magnetic core portion of finewire, a plurality of windings on said core portion, a U- shaped magneticcore portion having its ends in magnetic relation to the ends of saidstraight portion to form a substantially closed magnetic path, aone-piece shell of cast metal encasing each of said core portions topermanently seal. the same, and circuit terminals embedded in one ofsaid shells.

4. An induction coil made up of a straight core portion and a curvedcore portion forming a single magnetic path, windings in inductiverelation to said path, and a one-piece 'cast metal shell encasing eachof said core portions and having an integral metal bracket forming amounting therefor.

5. An induction coil comprising a straight core portion of fine wire, aplurality of windings on said portion, a curved core arranged to embracesaid straight portion but spaced therefrom at each end, a one-piece castmetal shell enclosing each of said core portions, means for detachablysecuring said shells together and terminals carried by one of saidshells.

6. An induction coil comprising a closed magnetic path made up of astraight portion and a curved portion, a plurality of windings ininductive relation to said path, a cast metal shell encasing saidstraight portion, a similar shell enclosing said curved portion, circuitterminals carried by said housing and connected with said windings, andmeans for detachably securing said portions in magnetic relation.

7. An induction coil comprising a straight magnetic core portioncarrying windings, a cast metal shell surrounding said core portion andcarrying integral terminal extensions, a regulating resistance on one ofsaid extensions and connected with one of said windings, a curvedmagnetic core portion embracing said straight portion and coope'atingtherewith. to form a substantially closed magnetic path, a cast metalshell inclosing said curved core. portion, and circuit terminals mountedon one of said shells and connected to certain of said windings.

8. An induction coil comprising a magnetic core of fine wire made up ofa straight portion and a curved portion separated by air-gaps, windingson said straight portion, a combined integral enclosing casing and basecomprising a metal shell cast around said windings and said core topermanently seal the same, a similar shell surrounding said curvedportion, and means for detachably securing said shells together.

CURT FREDERICK REIS.

